FIGS. 6 to 10 each show an example of a conventional semiconductor device. FIG. 6 is a top view showing the principal portions, FIG. 7 a cross-sectional diagram of the principal portions, taken along line X1-X1 of FIG. 6, FIG. 8 a cross-sectional diagram of the principal portions, taken along line X2-X2 of FIG. 6, FIG. 9 a cross-sectional diagram of the principal portions, taken along line Y-Y of FIG. 6, and FIG. 10 a cross-sectional diagram of the principal portions in which external wiring 75 is connected to a semiconductor device 500. FIG. 6 is a top view of the principal portions, with a lid 72 being removed from an upper part of the semiconductor device, in which wiring for a semiconductor chip 73 is not shown.
This semiconductor device 500 has a semiconductor module 51 and a cooler 52. The semiconductor module 51 has a resin frame 55. This resin frame 55 is mounted with external conductive terminals 53 with first fixing holes 54, and nut portions 57 that are disposed under the first fixing holes 54 and have screw holes opened therein. In addition, as shown in FIG. 7, a second fixing hole 83 for fixing the semiconductor module 51 and the cooler 52 is formed in each of the four corners of the resin frame 55. A metal tube 82 and the like are disposed in an upper inner circumference of each of the second fixing holes 83. Through-holes 81 of the metal tubes 82 form parts of the second fixing holes 83. The cooler 52 has a top plate 59 disposed under the semiconductor module 51, and a bottom plate 63 having screw portions 66 for fixing the top plate 59. The semiconductor module 51 and the cooler 52 are fixed to each other with bolts 84 inserted through the second fixing holes 83. A plurality of fins 62 is disposed on the lower surface of the top plate 59. A space surrounded with the top plate 59 and bottom plate 63 is formed as a refrigerant passage 70 through which a refrigerant such as water flows. The lower surface of a DCB (Direct Copper Bonding) substrate 74 is soldered to the upper surface of the top plate 59, and semiconductor chips 73 are adhered to the upper surface of the DCB substrate 74. Spaces inside the resin frame 55 are filled with a protective member 71 such as a gel.
The symbol “Lo” shown in the diagrams represents the width of the semiconductor device 500 as viewed in a planar direction, and the symbol “Mo” represents the length of the same. As the external conductive terminals 53 on the upper surface of the semiconductor device 500, P-terminals and N-terminals that receive input of a DC voltage are disposed side by side in a row in the lower section of FIG. 6, and three AC terminals that output a three-phase AC voltage are disposed side by side in a row in the upper section of FIG. 6.
As shown in FIG. 10, the external wiring 75 and the external conductive terminals 53 are fixed with bolts 67.
PTL 1 below discloses a structure in which a semiconductor device is thread-fastened to a heat sink through the inside of a package seat of the semiconductor device, with an insulation sheet interposed between the semiconductor device and the heat sink.
PTL 2 and PTL 3 below each disclose a semiconductor device that is screwed to a cooler through a part protruding to the outside of a semiconductor module.